What can photogrammetry do for cultural heritage? 7 practical use cases explained clearly

In the field of cultural heritage preservation and documentation, there is a strong desire to minimize damage to objects, accurately record their current condition, and organize information in a way that can be reviewed repeatedly afterward. The range of cultural heritage is broad—wooden buildings, stone structures, Buddhist statues, archaeological remains, gardens, old roads, historic sites—and each varies in shape, size, installation environment, and preservation condition. For that reason, traditional measured surveys and photographic records alone often cannot preserve all the necessary information.

Photogrammetry has attracted attention as a solution. Photogrammetry is a method that reconstructs the shape and spatial relationships of an object from multiple photographs and produces deliverables such as plan drawings, elevations, 3D models, point clouds, and orthophotos. It is relatively easy to adopt without special large-scale equipment and can be applied to cultural properties that are difficult to touch, so it has started to be used across a wide range of tasks including surveys, recording, preservation, restoration, and public presentation.

However, many practitioners may still feel uncertain about what photogrammetry can actually achieve for cultural heritage, worry that adopting it will only result in taking photos and nothing more, or want concrete examples of when it is useful. Photogrammetry is not just a way to create visually appealing 3D representations; it is a practical technology that contributes to improving the accuracy of records, comparative verification, drawing production, repair planning, and public use. The key is to envision the appropriate deliverables from the start and proceed with a well-organized shooting plan and data management approach.

This article explains the basics of photogrammetry for cultural heritage and then clearly outlines seven practical use cases that are useful in the field. It is intended to help those considering adoption as well as those who already take photographic records but want to use them more effectively.

Table of Contents

• What is photogrammetry for cultural heritage

• Why photogrammetry is attracting attention in the cultural heritage field

• Use case 1: Advanced record preservation

• Use case 2: Increased efficiency in drawing production

• Use case 3: Comparative verification before and after restoration

• Use case 4: Grasping deterioration and deformation

• Use case 5: Capturing ruins and terrain as surfaces

• Use case 6: Use in exhibition and public outreach

• Use case 7: Creating recovery materials for disasters and damage

• How to proceed to make photogrammetry for cultural heritage successful

• Perspectives needed to make photogrammetry useful on site

• Summary

What is photogrammetry for cultural heritage

Photogrammetry for cultural heritage involves photographing an object from multiple positions and angles and reconstructing its three-dimensional shape and positional information from common points in those photographs. Simply put, it is a technique that treats photos not just as record images but as data for measurement. This allows the object’s shape, size, surface condition, and spatial relationships to be handled quantitatively afterward.

The deliverables obtainable through photogrammetry in the cultural heritage field are highly diverse. For example, orthophoto images that present walls or floors as if viewed directly from above, 3D models expressing three-dimensional shapes, point cloud data with precise position information, and elevation and plan references that serve as bases for drafting are among the outputs. These can be used individually or expanded into survey reports, restoration plans, preservation records, explanatory materials, and exhibition content.

Photogrammetry is effective on cultural heritage sites because it enables information collection while minimizing contact. Some objects cannot easily be touched, scaffolding may be restricted, or large equipment may be difficult to use due to surrounding conditions. With a proper shooting plan, photogrammetry can respond relatively flexibly even under such constraints.

That said, photogrammetry is not just about taking many photos. Factors that affect the quality of results include required image overlap, minimizing blur, avoiding blind spots, handling scales and coordinates, and considering lighting conditions. To make photogrammetry practical in cultural heritage work, it is essential not only to aim for clean images but also to design the process with recording, analysis, and long-term use in mind.

Why photogrammetry is attracting attention in the cultural heritage field

One reason photogrammetry is attracting attention in the cultural heritage field is its adaptability to diverse preservation targets. Cultural heritage is not limited to buildings. Stone monuments, stone Buddhas, burial mounds, gardens, castle ruins, archaeological remains, murals, wooden statues, and decorative elements vary widely in shape, material, and environmental conditions. Photogrammetry’s relative versatility makes it easier to apply across this wide range and to construct recording methods tailored to each object.

Another reason is that it can preserve both shape and appearance simultaneously. In cultural heritage documentation, visual information such as color, surface weathering, cracks, repair traces, and material texture are as important as dimensions. Photogrammetry links shape data with imagery, making it easier to capture surface conditions that are difficult to convey with measured drawings alone. This expands its role from a mere aid to drawing to a comprehensive recording method.

Photogrammetry is also well suited for temporal comparisons. Preservation of cultural heritage often requires tracking changes in condition over years. If photogrammetry is carried out periodically under similar conditions, it becomes easier to identify differences in shape and surface condition and use them as indicators of deterioration. This helps determine whether repair is necessary before conditions worsen.

In addition, photogrammetry’s outputs are easy to share. Cultural heritage work involves owners, managers, surveyors, designers, contractors, administrative staff, and exhibition staff, among others. Photogrammetry deliverables—drawings, images, and 3D data—are visually communicative, helping align understanding among stakeholders. They make it easier to share site conditions with people who have not seen the site, thereby improving decision-making quality.

Use case 1: Advanced record preservation

The most fundamental and important use case for photogrammetry in cultural heritage is the advancement of record preservation. Traditional photographic records are effective at preserving the appearance at the time of shooting but are limited when it comes to checking dimensions later or re-examining from different viewpoints. By using photogrammetry, the photo set itself becomes measurement source data, facilitating reanalysis and additional checks.

For example, inscriptions and patterns carved on stone surfaces, deformations of wooden elements, jointing of building components, and subtle elevation differences on archaeological surfaces—information that is easy to overlook in ordinary photos—can be preserved as three-dimensionally organized deliverables. The shift from merely “being photographed” to “retained with spatial relationships” is a major difference. This difference has great value when re-surveying or reorganizing records in the future.

The quality of record preservation also directly affects the ability to pass on cultural heritage. If on-site knowledgeable staff are transferred or personnel involved in a survey change, past decisions and the intent behind records can be hard to convey. When photogrammetry captures spatial relationships and the overall appearance, successors can more easily grasp the prior state. This reduces reliance on individual memory and supports organizational knowledge transfer.

Because the purpose of cultural heritage preservation is to leave things for the future, temporary report-style records are insufficient. Records must be meaningful when revisited years or decades later. Photogrammetry is effective for building that foundation and is highly valued as a means to preserve the current condition from multiple perspectives.

Use case 2: Increased efficiency in drawing production

Cultural heritage surveys and preservation tasks require various drawings such as plans, elevations, sections, and development drawings. However, cultural heritage objects are often irregular in shape, and simple dimensional measurements alone may make drawing difficult. Photogrammetry allows you to capture shape information over surfaces that serve as the basis for drawing, improving both the efficiency and accuracy of producing drawings.

For example, stone walls, stone steps, foundation stones, statues, decorative carvings, and elevations of historic buildings have complex undulations and inclinations that are time-consuming to document accurately by manual on-site work alone. Using orthophotos and 3D data from photogrammetry, you can efficiently prepare the base information for drawings while confirming dimensional and positional relationships. Information that could not be fully captured on site can be supplemented in the data later, which is a major advantage.

Improving drawing production efficiency does not only mean saving time. Access restrictions, opening schedules, weather, and scaffolding conditions often prevent personnel from staying on site for long periods. Rather than trying to complete everything on site, it is better to secure broad information during shooting and move much of the organization and drafting to subsequent steps. Photogrammetry fits well with this approach and reduces on-site burdens.

Photogrammetry-based drawings also tend to be more communicative. Drawings for cultural heritage are used not only to show dimensions but also as reference materials for damaged areas, repair history, design features, and scope of work. Drawings based on photogrammetry make it easier to map current conditions to the drawings, which is useful in meetings and report preparation.

Use case 3: Comparative verification before and after restoration

In restoration and preservation work, it is important to accurately document the pre-work condition and clearly record what changes occurred after the work. Photogrammetry is well suited to this kind of before-and-after comparative verification because it makes it easy to compare not only visual impressions but also spatial relationships and shape changes.

For example, bulging in wall surfaces, displacement of components, surface delamination, missing stone elements, and ground settlement may be visually identifiable before work but are not easy to quantify in terms of how much they improved afterward. If photogrammetric data are prepared for both before and after restoration, it becomes easier to compare the same locations and share the nature of changes among stakeholders.

Photogrammetry also increases the transparency of the restoration itself. In cultural heritage restoration, it is important to be able to explain later which parts received which treatments and why those decisions were made. Using photogrammetry results makes it easier to organize pre-treatment conditions, the scope of treatment, and post-treatment states, strengthening the persuasiveness of records and helping researchers, restorers, and managers share a common understanding.

Furthermore, photogrammetric records support future re-restoration and monitoring. Restoration is not necessarily a one-time event; environmental changes and material aging can necessitate further action. High-precision records from the time of restoration can be used as reference material for future decisions. In other words, photogrammetry provides baseline documentation that supports the long-term continuity of cultural heritage maintenance.

Use case 4: Grasping deterioration and deformation

In preservation management, responding only after a problem becomes large can be too late. Early detection of small cracks, tilting, wear, surface delamination, water effects, and vegetation intrusion is crucial. Photogrammetry can be used to monitor such deterioration and deformation.

It is particularly effective to record the same object at regular intervals and track signs of change. Regular photographs can provide temporal comparison, but small differences in shooting position or angle can change the perceived appearance and make accurate comparisons difficult. Photogrammetry organizes the entire object three-dimensionally or orthorectifies specific surfaces, making it easier to standardize comparison criteria. This makes it easier to notice changes in surface condition and subtle differences in shape.

For example, when a stone monument’s surface becomes rounded due to weathering, wooden components develop warping or twisting, parts of a wall show signs of detachment or flaking, or ground around ruins is slowly eroding, the quality of regular records influences judgment. Incorporating photogrammetry allows managers to accumulate comparable materials rather than relying solely on staff experience.

Of course, photogrammetry alone cannot diagnose all causes of deterioration. It should be combined with material testing, structural analysis, and environmental monitoring. Nevertheless, it is an effective entry point for detecting anomalies early and organizing priorities for further investigation. Protecting cultural heritage requires not just finding abnormalities but sharing the observed state and linking it to the next decision. Photogrammetry plays that bridging role.

Use case 5: Capturing ruins and terrain as surfaces

While cultural heritage often conjures images of buildings and art objects, many targets are spatial and expansive, such as archaeological sites, burial mounds, castle ruins, gardens, approach routes, terraces, and groups of stone walls. For such subjects, it is important to understand not only individual components but also overall layout, elevation differences, and relationships with the surroundings. Photogrammetry excels at capturing ruins and terrain as surfaces.

For instance, when recording archaeological surfaces after excavation, conditions change as excavation progresses, so it is necessary to document wide areas quickly. Photogrammetry that captures the whole site later makes it easier to review the positional relationships and shapes of structures. Even in gardens and historic sites with undulating terrain, photogrammetry clarifies three-dimensional characteristics that are hard to convey with flat photographs.

Capturing surfaces is also useful for preservation and maintenance planning. When considering visitor flow, areas prone to drainage problems, vegetation management extents, and priority repair points, seeing the whole picture is a prerequisite. Wide-area results from photogrammetry often serve as foundational materials for those evaluations.

Moreover, for expansive cultural heritage, looking only at parts may obscure essential meaning. A section of ruins that looks like a mere depression or row of stones might be understood as an important component when seen in the context of the overall layout. Photogrammetry makes such spatial contexts more visible, adding value to both recording and interpretation.

Use case 6: Use in exhibition and public outreach

Photogrammetry of cultural heritage can be applied not only to preservation and research but also to exhibition and public outreach. To convey the value of cultural heritage widely, records that only specialists can understand are insufficient; materials need to be presented in ways accessible to general visitors and local residents. 3D models and well-organized image materials generated by photogrammetry are effective for this type of communication.

For example, details in high places that are normally inaccessible, reverse sides, damaged areas, and relationships with internal structures can be presented as intuitive, model-like materials. These supplements help improve the quality of exhibition explanations by providing information that may be difficult to grasp on site. Photogrammetry is also useful for visually showing differences before and after restoration or illustrating historical changes over time.

In terms of public use, photogrammetry also supports balancing preservation with access. Some cultural properties pose risks from contact or proximity. By enriching alternative observation materials through photogrammetry, information can be shared while taking preservation into account. Educational outreach and regional promotion often require materials that can be understood visually rather than explained with technical jargon; photogrammetry outputs are highly versatile for such purposes.

Furthermore, deliverables created for exhibitions and public use can be repurposed for internal tasks. 3D visualizations and orthophotos prepared for visitors are easily adapted for briefing materials, stakeholder reports, and sharing conservation plans. Rather than treating research and public outreach as separate, it is increasingly important to deploy a single data foundation across multiple uses in cultural heritage practice.

Use case 7: Creating recovery materials for disasters and damage

Cultural heritage is exposed to various risks such as earthquakes, heavy rain, typhoons, fires, falls, and contact accidents. When damage occurs, a key starting point for recovery is how accurately the pre-damage condition was recorded. In this respect, photogrammetry is highly valuable for producing recovery materials after disasters or damage.

Photos taken after damage may not be sufficient to accurately reproduce original shapes or joinery. In particular, positional relationships of components, fine details of shapes, surface ornamentation, and how elements fit with their surroundings can be difficult to judge without pre-event records. If photogrammetric records are kept during normal times, recovery strategies can be developed with reference to the pre-disaster state.

Photogrammetry is also effective for emergency recording immediately after damage. Even when the site is unstable and hard to approach, shooting can capture a broad view of conditions and provide a starting point for organizing the extent of damage. In sites at risk of secondary damage, quickly acquiring a large amount of information is important. The sooner initial records are taken, the easier subsequent decisions and external explanations become.

In cultural heritage preservation, record compilation is often postponed due to budget and personnel constraints. But the true test of value comes when unexpected events happen. Photogrammetric pre-recording is both part of routine work and a preparedness measure for future crises. Protecting cultural heritage is not just about admiring the current state; it is also about preparing for the possibility of loss.

How to proceed to make photogrammetry for cultural heritage successful

To achieve results with photogrammetry for cultural heritage, clarifying the objective is the essential first step. Required shooting density and management methods vary depending on whether the goal is record preservation, drawing production, deterioration comparison, or exhibition use. If shooting begins with an unclear purpose, problems such as “we lack this angle,” “there is no scale reference,” or “essential parts are missing” are likely to arise later.

Next, understanding the characteristics of the subject is important. Cultural heritage can include reflective materials, fine relief, repetitive patterns, narrow spaces, elevation differences, and dark areas—conditions that present challenges for photogrammetry. Therefore, confirm the object’s size, material, surrounding environment, reachable areas, and lighting conditions in advance and design a feasible shooting plan.

Additionally, designing how deliverables will be managed is indispensable. If shooting data, processed data, output images, drawing bases, and explanatory materials are managed separately, future reuse becomes difficult. Since cultural heritage records are intended for long-term storage, it is important to archive items such as shooting date and time, object name, location, personnel, and reference information used. Even if the data remain, they are of limited practical use without appropriate context.

Furthermore, how to link site coordinates and position information is an important practical point. Photogrammetry for cultural heritage can expand beyond single-object shape capture to include layout of ruins, relationships within a site, and comparisons with past data. Therefore, making outputs easy to overlay with other data in later steps greatly expands their applicability.

Perspectives needed to make photogrammetry useful on site

To make photogrammetry truly useful in practice, designing its use is more important than the technology itself. A common failure is making shooting or 3D creation the objective, without linking them to subsequent preservation management or explanatory work. Even if results look good, they will not be adopted in practice if they are difficult to convert into drawings, compare, or share.

For that reason, the end use must be decided from the outset. Consider which forms or reports will use the outputs, which drawings they will inform, who will view them, and how comparisons will be made in the next survey. Doing so clarifies shooting priorities and required accuracy. In cultural heritage practice, being organized into a usable form is often more important than technological sophistication.

Ease of position management on site should not be overlooked. Records of cultural heritage require not only single-object shapes but also relationships with the site and surroundings, overlaying past data, and indicating repair scopes. When photogrammetry outputs can be handled together with positional information, the operational value of records significantly improves.

If you want to streamline positioning and sharing on site, it is also useful to reconsider how positioning references are obtained alongside photogrammetry. For example, in cases where you want to quickly capture record points or checkpoints around cultural heritage to facilitate later data alignment, high-precision GNSS positioning devices that attach to an iPhone, such as LRTK, can be helpful. Linking photogrammetry shooting plans and deliverable organization with on-site position information makes it easier to integrate photographic records into ongoing management rather than leaving them as one-off tasks.

Summary

What photogrammetry can do for cultural heritage is more than mere 3D visualization. It touches many practical aspects of cultural heritage work: advancing record preservation, increasing efficiency in drawing production, comparative verification before and after restoration, detecting deterioration and deformation, organizing ruins and terrain as surfaces, expanding exhibition and public outreach, and creating recovery materials in the event of disasters. The important thing is not simply taking attractive photos but designing from the start why the records are made and how they will continue to be used.

Many cultural heritage items cannot be restored once lost, and therefore the quality of records influences future decisions. Photogrammetry is a powerful means to preserve the current state from multiple angles, share it among stakeholders, and create materials that remain useful over time. If you are about to undertake photogrammetry for cultural heritage, planning should include the intended uses of deliverables and how to handle positional information to maximize the benefits of adoption.

If you want to further improve on-site recording accuracy and operational usability, consider combining photogrammetry with on-site position information rather than relying on photogrammetry alone. LRTK, as an iPhone-mounted high-precision GNSS positioning device, can streamline management of reference points around cultural heritage and the sharing of positions, and it pairs well with photogrammetry to connect results to on-site operations. To make preservation records assets that are used continuously rather than just being photographed and filed, it is important to establish systems that address both photogrammetry and position management.